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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script type="text/javascript">
        // function A() { }
        // A.prototype.n = 1
        // var b = new A() 
        // A.prototype = {
        //     n: 2,
        //     m: 3,
        // }
        // var c = new A()
        //         //   1    u    2    3
        // console.log(b.n, b.m, c.n, c.m)

        function Foo() {
            Object.prototype.a = function () {
                console.log('可访问a')
            }
        }
        Function.prototype.b = function () {
            console.log('可访问b')
        }
        var foo = new Foo()
        foo.a();//可访问a
        foo.b();//gg
        Foo.a();//a
        Foo.b();//b

    </script>
</body>
</html>